Answer: 1. Mark needs to earn more than $45 in order to buy a new hockey uniform.
Step-by-step explanation: The number line shows an open circle on 45 with a line pointing to the right.
An open circle means that the number is greater than or less than the number that the circle is over. That means that the total is greater than or less than $45.
In case you run into a similar problem, note that a filled-in circle (completely black) means that the total is greater than or equal to, or less than or equal to the number the circle is over.
How do we know if it is more than or less than $45? Well, the direction that the line points tells us. You can see a dark arrow pointing to the right of the 45, meaning that the total is more than $45. If the arrow was pointing to the left, that would have meant that the total was less than $45.
You can tell that the left side indicates a smaller number as you can see a 40, a number which is less than 45, to the left of 45 on the number line. This allows us to assume that the right side of 45 is greater than 45.
With this information, we can conclude that the number line is showing a number greater than 45. If we use this information, we can figure out what answer choice is right.
The first option says, "Mark needs to earn more than $45 in order to buy a new hockey uniform." Does this sound familiar? The number line says that the total is greater than 45, similar to how Mark needs more than $45.
The second option says, "Lisa earned less than $45 babysitting last month." Well, our number line points to the right, signifying that the number is greater than 45. Lisa earned less than $45 though, which does not match the number line.
In conclusion
Remember three things:
1. An open circle means that the number is greater than or less than the number that the circle is over
2. A closed circle means that the number is greater than or equal to or less than or equal to the number that the circle is over
3. If the dark arrow points to the right, the number is greater than (or in the case of a filled circle, greater than or equal to) the number that the circle is over.
If the dark arrow points to the left, the number is or less than (or in the case of a filled circle less than or equal to) the number that the circle is over.